C#中检查ListDictionary是否包含特定的键
要检查ListDictionary是否包含特定键，代码如下-
示例
using System;
using System.Collections;
using System.Collections.Specialized;
public class Demo {
public static void Main() {
ListDictionary dict1 = new ListDictionary();
dict1.Add("A", "Books");
dict1.Add("B", "Electronics");
dict1.Add("C", "Smart Wearables");
dict1.Add("D", "Pet Supplies");
dict1.Add("E", "Clothing");
dict1.Add("F", "Footwear");
Console.WriteLine("ListDictionary1 elements...");
foreach(DictionaryEntry d in dict1) {
Console.WriteLine(d.Key + " " + d.Value);
}
ListDictionary dict2 = new ListDictionary();
dict2.Add("1", "One");
dict2.Add("2", "Two");
dict2.Add("3", "Three");
dict2.Add("4", "Four");
dict2.Add("5", "Five");
dict2.Add("6", "Six");
Console.WriteLine("\nListDictionary2 key-value pairs...");
IDictionaryEnumerator demoEnum = dict2.GetEnumerator();
while (demoEnum.MoveNext())
Console.WriteLine("Key = " + demoEnum.Key + ", Value = "+ demoEnum.Value);
Console.WriteLine("Is the ListDictionary having fixed size? = "+dict2.IsFixedSize);
Console.WriteLine("If ListDictionary read-only? = "+dict2.IsReadOnly);
Console.WriteLine("Is ListDictionary synchronized = "+dict2.IsSynchronized);
Console.WriteLine("The ListDictionary has the key 5? = "+dict2.Contains("5"));
}
}输出结果
这将产生以下输出-
ListDictionary1 elements... A Books B Electronics C Smart Wearables D Pet Supplies E Clothing F Footwear ListDictionary2 key-value pairs... Key = 1, Value = One Key = 2, Value = Two Key = 3, Value = Three Key = 4, Value = Four Key = 5, Value = Five Key = 6, Value = Six Is the ListDictionary having fixed size? = False If ListDictionary read-only? = False Is ListDictionary synchronized = False The ListDictionary has the key 5? = True
示例
让我们看另一个例子-
using System;
using System.Collections;
using System.Collections.Specialized;
public class Demo {
public static void Main() {
ListDictionary dict = new ListDictionary();
dict.Add("1", "SUV");
dict.Add("2", "Sedan");
dict.Add("3", "Utility Vehicle");
dict.Add("4", "Compact Car");
dict.Add("5", "SUV");
dict.Add("6", "Sedan");
dict.Add("7", "Utility Vehicle");
dict.Add("8", "Compact Car");
dict.Add("9", "Crossover");
dict.Add("10", "Electric Car");
Console.WriteLine("ListDictionary elements...");
foreach(DictionaryEntry d in dict) {
Console.WriteLine(d.Key + " " + d.Value);
}
Console.WriteLine("\nIs the ListDictionary having fixed size? = "+dict.IsFixedSize);
Console.WriteLine("If ListDictionary read-only? = "+dict.IsReadOnly);
Console.WriteLine("Is ListDictionary synchronized = "+dict.IsSynchronized);
Console.WriteLine("The ListDictionary has the key M? = "+dict.Contains("M"));
}
}输出结果
这将产生以下输出-
ListDictionary elements... 1 SUV 2 Sedan 3 Utility Vehicle 4 Compact Car 5 SUV 6 Sedan 7 Utility Vehicle 8 Compact Car 9 Crossover 10 Electric Car Is the ListDictionary having fixed size? = False If ListDictionary read-only? = False Is ListDictionary synchronized = False The ListDictionary has the key M? = False